Old Colony is offering something called TLwrx Version 3.0
Transmission Line software by G. L. Augspurger.

I never even heard of it before much less 3 point Oh.

Ad is on page 44 of May '04 ish.

I did a quick search of Old Colony and found they also publish books from Bill Fitzmaurice and Charles Hansen, both of whom are very active in audio discussion groups and the DIY community in general. They've also distributed material from Bruce Rozenblit, Vance Dickson, Joseph D'Appolito, David Weems, Robert Bullock and Robert White, among others.

So Old Colony seems like a pretty cool publisher.

So I have seen the Old Colony book list before. But in all
these years I have not seen much about what might be a
competitive program to the work of Martin King. Auspurger is
referred to in technical articles, but an implementation of a
design program, to my knowledge, was never written up in
_aX_. I would have to check my old issues. _aX_ is now available
on cd rom for subscribers to the print version.

BTW Old Colony is also reprinting the complete monthly
publication called ... name escapes me.... in 2 volumes from the '70s. This magazine had all the breakthrough work for the emerging
audiophile community.

Anyone can get the Old Colony cataloge from a request to
www.custserve@audioXpress.com.